A multi chamber system that is semiconductor processing equipment has been known. The multi chamber system includes a plurality of semiconductor processing chambers and a load lock chamber. Each of the semiconductor processing chambers and the load lock chamber is connected to one transferring room via a gate, and a transferring apparatus is arranged in the transferring room. One example of the transferring apparatus is a transferring apparatus including two hands, which is disclosed in Japanese Laid-Open Patent Application Publication No. 2009-50986.
This transferring apparatus includes a revolving base and two arms. The revolving base is rotated by a revolution drive unit. The two arms are rotatably attached to the revolving base. The two arms are connected to one arm drive unit via, for example, a transmission belt. The arm drive unit is configured to drive the transmission belt to rotate the two arms in conjunction with each other. The hand capable of holding a wafer is formed at a tip end portion of each of the arms which operate in conjunction with each other.
In accordance with the transferring apparatus configured as above, the arm drive unit rotates the arm while the revolution drive unit rotates the revolving base. Thus, the transferring apparatus transfers the semiconductor wafer held by the hand. As above, the transferring apparatus capable of transferring the semiconductor wafer takes the semiconductor wafer from the load lock chamber and the semiconductor processing chamber, transfers the semiconductor wafer to a predetermined mounting position of the next semiconductor processing chamber, and mounts the semiconductor wafer on the mounting position. The semiconductor wafer having been transferred to the mounting position is subjected to a predetermined process treatment and is then further transferred to the next mounting position by the transferring apparatus.
Because of its configuration, the transferring apparatus described in Japanese Laid-Open Patent Application Publication No. 2009-50986 can transfer the semiconductor wafer only radially about a revolution axis that is a revolution center of the revolving base. Therefore, even if the transferring apparatus described in PTL 1 transfers the semiconductor wafer in a case where the mounting positions are radially arranged and the gates face the revolution center, the semiconductor wafer and the arm do not contact the gates. However, since the mounting positions and the directions of the gates change depending on contents of the process treatments, the shapes and positions of the semiconductor processing chambers, and the like, the gates are not always facing the revolution center. If the transferring apparatus described in PTL 1 transfers the semiconductor wafer in a case where the gate is not facing the revolution center, the hand obliquely approaches to the gate, and the semiconductor wafer and the arm contact the gate. Such contact of the semiconductor wafer and the arm is avoidable by widening the gates of the semiconductor processing chambers. However, in such case, the outer diameter of the transferring room increase, and the semiconductor processing equipment increases in size.
Here, an object of the present invention is to provide a transferring apparatus capable of inserting a wafer into a gate substantially linearly regardless of the position on which the wafer is mounted and the direction of the gate.